Lunar Lake Thunderbolt 4 compatibility workaround do not work

[James0G]

This is a follow up to Lunar Lake thunderbolt 4 compatibility issues - Intel Community.

So I tried the solution you provided, I shutdown the system, connected the eGPU device, and then booted the system. But the external GPU is still not recognized.

I mean, after using the workaround, the system performs better than before when the eGPU dock is plugged in after booting. The laptop no longer loses trackpad, wifi and audio, the Intel PCI Express upstream port is also started normally, and windows can even recognize the USB Hub on the eGPU dock, but the eGPU is still not recognized.

Any Idea?

[VonM_Intel]

Hi, James0G.

Thank you for posting in our Community and for providing an update on the troubleshooting steps. I'm glad to hear that the workaround has improved the system’s behavior by restoring functionality to the trackpad, Wi-Fi, audio, and PCI Express upstream port. However, I understand that the eGPU is still not being recognized, and I’m here to help you move forward. 

In the meantime, I see your concerns and I'll get back to you as soon as possible.

Have a nice day!

Best regards,

Von M.

Intel Customer Support Technician

[VonM_Intel]

Hello, James0G.

Thank you for your patience as we continue troubleshooting your Thunderbolt connection and GPU detection issue. After reviewing the case, I determined that while the Thunderbolt connection is partially functional, the GPU is not being properly initialized.

To further diagnose the issue, please try the following additional troubleshooting steps:

1. Check Device Manager

• Open Device Manager and look under Display adapters and Other devices to see if the GPU appears (even with a yellow warning sign).
• If it shows up with an error, what is the error code?

2. Update Thunderbolt & GPU Drivers

• Thunderbolt: Make sure you have the latest Thunderbolt drivers and firmware from ASUS.
• GPU: Update both the internal GPU (Intel Arc or Iris Xe) and the external GPU (NVIDIA/AMD).
• Chipset drivers: Update Intel chipset drivers and Management Engine Interface (MEI).

3. Enable eGPU in Thunderbolt Control Center

• Open Thunderbolt Control Center and see if the eGPU is detected.
• If it's listed, manually approve it (if security settings require approval).
• If it's not detected, check BIOS settings (see step 6).

4. Check Power & Cables

• Ensure the eGPU dock is receiving enough power.
• Try a different Thunderbolt 4 cable (some cables only support USB4 speeds, not full PCIe bandwidth).

5. Try Hot-Plugging the eGPU

• Since the system no longer crashes, try plugging in the eGPU after booting into Windows and see if it gets detected.

6. BIOS Settings

• Check if there’s a BIOS update available for your laptop.
  • Some BIOS settings might affect eGPU functionality:Thunderbolt Boot Support → Enable
  • PCIe Resource Allocation → Try different modes (if available)
  • Security settings → Ensure Thunderbolt security is not blocking PCIe devices

7. Check Windows & Power Settings

• In Power Options, set PCI Express Link State Power Management to Off.
• Disable Fast Startup in Windows (Control Panel → Power Options → Choose what the power buttons do).

8. Try an Older Thunderbolt Driver

• Some users have reported that older Thunderbolt drivers work better than the latest ones on Lunar Lake systems. Try rolling back to an earlier version if updates don’t help.

9. Test eGPU on Another System

• If possible, test the eGPU dock on another Thunderbolt 3/4-compatible laptop to see if it gets recognized.

Kindly let me know the results. 

Best regards,

Von M.

Intel Customer Support Technician

[James0G]

Hi Von,

First, the eGPU doesn't show up in the device manager. I've updated the Thunderbolt driver, motherboard driver, and built-in GPU to the latest versions through MyASUS and the Intel Driver Support Assistant.

I've also tried replacing the eGPU dock's power supply and Thunderbolt cable, but with the same result. The same eGPU dock configuration worked fine on my old laptop (Lenovo Yoga 14c with an Intel Core i7-1065G7 CPU).

I don't fully understand what you mean by "Hot-Plugging the eGPU". Do you want me to test something like "power off the system, connect the eGPU dock without the GPU, power on the system, then plug in the GPU"? If so, this would be very difficult to test, the eGPU dock is a closed box and it's hard to plug in the GPU while the system is powered on.

The BIOS has been updated to the latest version, and ASUS has not provided an updated test BIOS. There are not many Thunderbolt-related options in the BIOS. I have tried changing some of them, but nothing has changed.

In addition, can you provide the Thunderbolt Control Center installation program? I can't find this application in the new system. It seems that there is no such application on the Intel official website or the Microsoft Store， although there is such a program on my old laptop.

[VonM_Intel]

Hello, James0G.

Have you had a chance to review my previous response? Please let us know if you require any further assistance. I'm here to help.

Best regards,

Von M.

Intel Customer Support Technician

[VonM_Intel]

Hello, James0G.

Thank you for the detailed information. It really helps in diagnosing the issue. Given the steps you've already taken, it seems like you're dealing with a compatibility or configuration issue that needs further troubleshooting. Regarding the "hot-plugging" reference, I understand that it's difficult to unplug the GPU from a closed dock while the system is powered on. In this context, the suggestion would have been to try connecting the eGPU dock (without the GPU) first, power on the system, and then plug in the GPU afterward. This can sometimes help reset the Thunderbolt connection and establish proper communication. However, I realize this might not be feasible with your eGPU dock setup, so no worries if it isn't possible to test that way.

I’ll need to conduct additional research on this issue and will post an update in this thread once I have more information about this matter.

Best regards,

Von M.

Intel Customer Support Technician

[Tnci]

Allow me to add my experience to the list at it is almost exactly the same as JamesOG.

I am also using an ASUS Zenbook S14 from 2025 with Intel(R) Core(TM) Ultra 7 258V.

The eGPU is a Razer Core X with RTX 3070 inside.

If I plug the eGPU while the computer is running, it stops Wifi connection, audio, bluetooth and trackpad.

The same happens if I unplug then plug again the eGPU while the PC is ON.

If I connect the GPU before starting the PC, it works a bit better with all internal components behaving correctly but the eGPU is not recognized (fans running but no connection).

eGPU and RTX 3070 only appear in device manager when you select the hidden devices.

I tried deleting them, updating the drivers, nothing does the job.

I have tried the same eGPU setup tonight on another older laptop (Dell XPS 13 runing Intel older chip) and it works as expected.

So I am ruling out a faulty eGPU.

The ASUS Bios is very minimal regarding Thunderbolt or PCIe options.

It has been updated today actually with no better behaviour.

Nothing from all the options of your previous reply seems to work on my setup.

[VonM_Intel]

Hello, James0G.

I appreciate your continued patience while investigating the issue with your external GPU (eGPU) not being recognized via Thunderbolt 4. Following an in-depth analysis, my findings indicate that the root cause is likely related to how Thunderbolt 4 is integrated into the system’s motherboard, rather than an issue stemming directly from the CPU itself. Specifically, this behavior often stems from one or a combination of the following factors:

• Driver incompatibilities

• BIOS configurations

• Thunderbolt 4 port implementation at the motherboard level

The failure in communication between the Thunderbolt 4 interface and the eGPU dock suggests a compatibility issue that is not being resolved through standard system-level troubleshooting. While the Lunar Lake processor may be indirectly involved, the evidence points more convincingly toward motherboard-level integration concerns. At this stage, as we have exhausted all available troubleshooting steps on our end, I recommend reaching out directly to the motherboard OEM (Original Equipment Manufacturer). They will have the necessary tools and firmware insights to investigate hardware-level integration and Thunderbolt 4 configuration more deeply.

@Tnci , I appreciate you for providing such a detailed account of your experience. I truly empathize with the frustration you're facing, especially given the steps you've already taken to troubleshoot and the similarity to previously reported cases. That said, in order to provide you with the most accurate and efficient assistance, I kindly ask that you initiate a new support thread specific to your configuration. While your situation closely mirrors that of another user @James0G , having a dedicated case allows us to focus on the nuances of your setup, such as your ASUS Zenbook S14, the Razer Core X with RTX 3070, and the unique behavior you’ve observed. This ensures your case is properly documented and escalated as needed, and it also prevents any confusion or miscommunication that can arise from cross-thread troubleshooting.

Best regards,

Von M.

Intel Customer Support Technician